We describe the first public data release of the Dark Energy Survey , DES DR1 , consisting of reduced single-epoch images , coadded images , coadded source catalogs , and associated products and services assembled over the first three years of DES science operations .
DES DR1 is based on optical/near-infrared imaging from 345 distinct nights ( August 2013 to February 2016 ) by the Dark Energy Camera mounted on the 4-m Blanco telescope at Cerro Tololo Inter-American Observatory in Chile .
We release data from the DES wide-area survey covering { \sim } 5000 \deg ^ { 2 } of the southern Galactic cap in five broad photometric bands , grizY .
DES DR1 has a median delivered point-spread function of g = 1.12 , r = 0.96 , i = 0.88 , z = 0.84 , and Y = 0.90 \mathrm { arcsec } FWHM , a photometric precision of < 1 % in all bands , and an astrometric precision of 151 ~ { } \mathrm { mas } .
The median coadded catalog depth for a 1.95 \arcsec diameter aperture at { S / N } = 10 is g = 24.33 , r = 24.08 , i = 23.44 , z = 22.69 , and Y = 21.44 \mathrm { mag } .
DES DR1 includes nearly 400 M distinct astronomical objects detected in { \sim } 10 { , } 000 coadd tiles of size 0.534 \deg ^ { 2 } produced from { \sim } 39 { , } 000 individual exposures .
Benchmark galaxy and stellar samples contain { \sim } 310 { M } and { \sim } 80 { M } objects , respectively , following a basic object quality selection .
These data are accessible through a range of interfaces , including query web clients , image cutout servers , jupyter notebooks , and an interactive coadd image visualization tool .
DES DR1 constitutes the largest photometric data set to date at the achieved depth and photometric precision .